As Russia tightens grip on Crimea, Ukraine navy comes under siege

SEVASTOPOL, Ukraine, March 3 (Reuters) - The new head ofUkraine's navy has been in the job for less than a day, but,like his fleet and parts of his country, he is already undersiege.

On Monday morning, Serhiy Haiduk told his men that hispredecessor, who defected to the pro-Russian authorities inCrimea the previous day, was wanted for treason.

In the evening, he was holed up behind the crumbling whitewalls of his headquarters with some well-armed Russian soldiersand at least 200 angry pro-Russian activists at his gates.

Meanwhile, two warships - all that what was left of hisfleet of around a dozen vessels - found themselves blocked intheir Black Sea berths in Sevastopol by a Russian minesweeper.

"A Russian commander went aboard the Ukrainian ships fortalks this morning. The ships tried to leave but couldn't andnow you can see that Russian minesweeper is blocking them," alocal tour guide, who shows people round the port, told Reuters.

Sevastopol is home to Russia's Black Sea Fleet and, sincethe 1991 collapse of the Soviet Union, the far smaller Ukrainiannavy has been based here too.

The two fleets have for years enjoyed friendly relations,but Moscow's decision to use troops to secure various militaryobjectives in Crimea has strained ties to breaking point.

In Sevastopol town, outside the Ukrainian naval base, twoyoung men who pro-Russian activists described as Russiansoldiers and who were wearing camouflage fatigues used byRussia's military, had taken up position in front of the gates.

Wearing balaclavas and shaking their heads every timesomebody tried to film them, one held a heavy machinegun and theother a Kalashnikov assault rifle.

Further, along the base's perimeter in what seemed to be anunfinished building, at least six more soldiers looked on.

A man who declined to give his name said the pro-Russiancrowd wanted Haiduk to come out and say he was with the peopleand not with the authorities in Kiev, the Ukrainian capital.

"He's hiding in there. The soldiers inside don't need tosurrender their weapons, but we need to know they are with us"he said.

Protesters, some of them from the local pro-Russian 'RussianBloc' party, waved Russian flags and the flag of the RussianNavy, along with some Soviet-era military banners.

On the walls of the base they had erected two posters. Oneread "Fascism will not pass", while the other called on theUkrainian military to "support the people".

The smell of alcohol hung in the air.

As the Russian national anthem blared out, two protesterssmiled as they held fighting dogs that strained at the leash.

"We just want the guys inside to cross over to the people'sside," Vladimir Branec, a 38-year-old mechanic, said. "This is apeaceful meeting." He added with a laugh: "They've already givenup twice and then changed their mind."

The Ukrainian soldiers must renounce the oath they had madeto Ukraine and swear loyalty to the people of Crimea, he said.

If Haiduk was thinking of emerging, he would have struggledto get far. Pro-Russian protesters had parked three cars rightin front of the gates, effectively blockading the base.

Earlier in the day, Haiduk had lined his men up and toldthem that his predecessor, Rear Admiral Denys Berezovsky, hadbeen relieved of his post and was facing treason charges.

Witnesses said the Ukrainian sailors had spontaneouslybroken into the national anthem and some had wept at the news.

As darkness fell and pro-Russian activists continued their"meeting", a young man whose brother - a Ukrainian sailor - wasstuck inside, challenged the protesters to explain themselves.

"Why are you doing this?" he asked. "The Russian soldiersare already looking after security. You don't need to do this."

A man who wanted to be identified only as Mikhail, a34-year-old businessman, said the Russian soldiers wereprotecting the base to ensure that "provocateurs" did not starta conflict.

"They are guarding the Ukrainian servicemen fromprovocations," he said. "If they leave ... any car couldapproach and shoot the place up, and if some 'for sale'correspondent filmed it and someone had a Russian flag in theirhand, it would be all over the media and the internationalcommunity would force the Russian fleet from here."